1. Field of the Invention
The invention relates to indicating power status of a host computer system and a monitor with light emitting diodes mounted on the monitor, and more particularly to communicating power status of the host computer system over a universal serial bus.
2. Description of the Related Art
As computer systems become more complex there has been an ever increasing effort to simplify the operation of the computer system. Early computers were difficult to use and understand. Typically, the computer was controlled with memorized keystrokes and command sequences. If the keystrokes were not memorized, the user was left with no alternative but to thumb through pages of documentation to find the elusive command.
Over time, the keyboards were enhanced to include function and control keys. However, the addition of keys to the original keyboard had certain drawbacks, such as additional confusion and a lack of consistency in their use. For many computer users, memorizing and typing in commands to the computer via the keyboard is awkward and complicated. Because of this, alternate data input devices to the keyboard have been developed.
One of the most popular of these alternate data input devices is a mouse. To maximize the usefulness of the mouse and to simplify entry of commands into a computer, a graphical operating system has been developed by Microsoft Corporation and others. By using the mouse, the user can move a pointer across the screen to select functional screen elements, such as a pull down menu, icon or button. However, as computer systems, operating systems and software applications have become increasingly powerful, many more menus, icons and buttons are available for selection by the user. Operating systems and software applications may require a user to navigate many "levels" of pull down menus or icons before reaching the desired function or command. Under these circumstances, instead of simplifying the entry of commands to the computers, the graphical user interface sometimes adds complexity and confusion. Thus, there is still a need for some input method or apparatus that increases "user friendliness" by reducing operator confusion when performing or executing certain system functions.
The computer industry is continually striving to provide additional computer enhancements to entice computer novices to purchase a computer system. Despite the near universal presence of the computer in the office environment, many people still are uncomfortable with computers and are reluctant to purchase or upgrade a home computer. Therefore, it is important for computer designers to add new features in a cost effective manner to new computer products, while at the same time giving the user a feeling of familiarity and comfort. For example, a CD-ROM drive in a modern computer often doubles as an audio CD player. A computer may also double as a VCR, television or a telephone answering machine. Other roles for the computer will inevitably develop. While the user may be familiar with the operation of these devices, the benefit of adding these functions into the computer is often undermined because the average user may be unable or unwilling to access the menus or controls to operate these enhanced features. For instance, to use the CD-ROM player as an audio CD player, a user is required to proceed with the mouse through multiple levels of icons or pull-down menus before a CD is loaded and ready to play. The user must then use the mouse to select "play music" from a menu or screen before music is played. Therefore, as the array of options increases, users will be faced with increasingly complex graphics user interfaces unless another solution is found.
One approach to solving the problem has been disclosed in U.S. patent application Ser. No. 08/846,333 entitled "Computer Interface With Hardwire Button Array," filed on Apr. 30, 1997 and assigned to Compaq Computer Corporation. That application discloses a set of button switches, referred to as a button array, mounted to the top of a mini-tower computer system. Each button in the array provides a particular control function, such as controlling the playback of CD's, answering telephone calls, and other desired system functions. To identify the functions controlled by the buttons, each button is labeled with alphanumeric characters or icons representing the function associated with the button. Some buttons also have a light emitting diode (LED) associated with it to indicate status.
Although using a button array is an effective solution to the problem, being able to easily access the buttons sometimes may be difficult if the mini-tower is not within reach. Without being able to easily access the button array, the user may be discouraged from using the buttons. Furthermore, if status information is presented with an LED but the mini-tower is not within a convenient viewing range, the status information goes unappreciated.
Another approach to solving the problem has been disclosed in U.S. patent application Ser. No. 08/667,582, entitled "Controlling Multimedia Aspects of a Computer," filed on Jul. 12, 1996 and assigned to Compaq Computer Corporation. That application discloses a monitor having a volume control knob on its front control panel. This, of course, is a hardware alternative to the software solution offered by the operating system which requires a mouse. Embedded within the monitor is a microcontroller for sensing rotation of the volume control knob and communicating the movement back to a host computer. A proprietary interface was developed between the monitor and the computer system. A signal is sent directly to an audio chip over a pair of spare wires in a conventional video graphics array (VGA) cable.
Although this is an outstanding concept, the design incurred a noticeable delay from the actuation of the volume knob to the audible response of the system due to a 40 ms delay requirement of the audio chip. This caused the audio system to respond slowly and unpredictably. Additionally, the method is not easily transportable to other computer systems due to the proprietary nature of the solution.
Yet another problem exists with respect to digital controls on the monitor. Typically, there are several dedicated buttons on the bezel of the monitor for controlling such screen functions as horizontal and vertical size and position, color contrast and brightness. In an effort to reduce costs, the dedicated buttons were replaced with multifunction buttons which allowed the user to select one of the functions to adjust from an on screen display (OSD) menu provided by a controller in the monitor. However, the menuing system was text based and cumbersome. Additionally, a special controller was required in the monitor to provide the on screen display which added to the cost. Therefore, it was desirable to provide a better user interface to monitor functions.